Lindsay Sandiford, 56, originally from Redcar, Teesside, was arrested in May last year after police in Bali said they found 10.6lb (4.8kg) of cocaine worth £1.6 million in the lining of her suitcase.

There were gasps of surprise at Denpasar District Court when the sentence was passed, as not even the prosecution had been seeking the death penalty.

Sandiford wept as she was led away and covered her face with a scarf. Previously, she claimed in court that she was forced into taking the drugs into the country by gangsters who were threatening to hurt one of her children.

Foreign Office minister Hugo Swire told the Commons: "We strongly object to the death penalty and continue to provide consular assistance to Lindsay and her family during this difficult time."

Mr Swire said "repeated representations" had been made to the Indonesian authorities and Foreign Secretary William Hague had raised the case with his counterpart in the country. He added: "We understand that under Indonesian law, Lindsay has at least two further avenues of appeal through the courts as well as an opportunity to apply for presidential clemency should these be unsuccessful."

Delivering the sentence, a panel headed by Judge Amser Simanjuntak concluded that Sandiford had damaged Bali's image as a tourist destination and weakened its anti-drugs programme. The judge told the court: "We found no reason to lighten her sentence."

Prosecutors said during Sandiford's trial that they were seeking a 15-year prison term.

In her witness statement, Sandiford said: "I would like to begin by apologising to the Republic of Indonesia and the Indonesian people for my involvement. I would never have become involved in something like this but the lives of my children were in danger and I felt I had to protect them."

Amnesty International described the sentence imposed on Sandiford as "cruel". Its UK campaigns director, Tim Hancock, said: "She is the second British citizen sentenced to death for drug offences in the last six months - an extremely worrying trend. The death penalty is the ultimate inhuman punishment, and Amnesty never condones its use, but handing out a penalty of death by firing squad for a non-lethal crime is cruel in the extreme."